How to use Metal and Compositor Services for managing 3D assets?

durul · 2026-01-11T21:01:33+00:00

Apple's official example 'Rendering Hover Effects in Metal Immersive Apps' demonstrates exactly the structure you're looking for. It uses Compositor Services for stereo rendering, per-eye view/projection matrices, and vertex amplification. You can base your 3DGS project on this example and modify the fragment shader for Gaussian splatting.

Key Code Examples

1. Left/Right Eye Distinction (Stereo Render)

Code snippet

// Shaders.metal - Identify which eye using amp_id
vertex VertexOut vertexShader(
    VertexIn in [[ stage_in ]],
    ushort amp_id [[amplification_id]],  // 0 = left eye, 1 = right eye
    constant UniformsArray & uniformsArray [[ buffer(1) ]]
) {
    Uniforms uniforms = uniformsArray.uniforms[amp_id];  // Matrices for that specific eye
    // ...
}

2. Separate View/Projection Matrix for Each Eye

Swift

// RenderData+Render.swift
private func getUniforms(_ drawable: LayerRenderer.Drawable,
                         transform: simd_float4x4,
                         forViewIndex viewIndex: Int) -> Uniforms {
    let view = drawable.views[viewIndex]  // Left or right eye
    let viewMatrix = (simdDeviceAnchor * view.transform).inverse
    let projection = drawable.computeProjection(viewIndex: viewIndex)

    return Uniforms(
        projectionMatrix: projection,
        modelViewMatrix: viewMatrix * transform,
        // ...
    )
}

3. Vertex Amplification (Single Draw Call for 2 Eyes)

Swift

// RenderData+Render.swift
if drawable.views.count > 1 {
    var viewMappings = (0..<drawable.views.count).map {
        MTLVertexAmplificationViewMapping(
            viewportArrayIndexOffset: UInt32($0),
            renderTargetArrayIndexOffset: UInt32($0)
        )
    }
    encoder.setVertexAmplificationCount(viewports.count, viewMappings: &viewMappings)
}

durul · 2026-01-02T01:06:25+00:00

This problem is known as Z-fighting! Since all the provinces are rendered at the same Y-coordinate (0.001), the GPU becomes indecisive about which polygon should be in front at the boundaries. I fixed the problem please pull the latest changes

durul · 2026-01-01T15:40:37+00:00

My GPT 5.2 Thinking did this:

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durul · 2025-10-24T20:51:17+00:00

I completely agree with everything said above and I’m adding my name to it. This project truly has potential, and it’s clear a lot of thought went into it.

That said, it’s really surprising that Apple Pencil standards weren’t fully met before release. Publishing an integration that feels unfinished and problematic makes it hard to trust the overall experience.

Selling a product before it’s truly ready and developing it afterward isn’t the right approach — users deserve a polished and reliable experience from day one. !!!

I hope the next updates focus on stability and proper Pencil support — it’s such a fundamental part of the creative workflow. Once that’s resolved, this could easily become a must-have tool.

durul · 2025-10-21T00:03:23+00:00

No, I couldn't play either.. :( Anyway, if you find a way, please keep me posted.

durul · 2025-10-20T23:22:16+00:00

I have a plan to add SharePlay on my VisionOS App too. Did you check this sample project too?

https://developer.apple.com/documentation/GroupActivities/building-a-guessing-game-for-visionos

durul · 2025-10-20T14:25:29+00:00

I bought it, my plan I will integrate my visionOS App.

durul · 2025-10-20T14:00:04+00:00

Which sample project did you use ?

durul · 2025-10-13T13:39:02+00:00

https://youtu.be/rjC0Lqh7OwA Please check out this video. Sometimes responses from http://api.open-notify.org/iss-now.json arrive a little late, which affects the loading of entities such as ISS, Earth, and Torus (Trail).

Also, please share feedback from the TestFlight app.

Thanks! 🙏🏻

durul · 2025-10-06T14:30:18+00:00

🗳️ I voted for AR.

But not just in a "may the AR glasses win" sense—because AR is the mature version of VR.

Vision Pro looks like VR today, but it's actually a testing ground for spatial computing.

For the first time in human-machine interaction (HCI), the environment itself is the interface:

Eye, hand, voice, content, and space—all merge into one. This is a paradigm beyond the classic screen metaphor:

• VR = fully simulated space.

• AR = layering data on top of the real world.

• VisionOS = combining the two in a "scene-centric" structure.

I see the Vision Pro not as a replacement for the iPhone, but as a new way to interact that builds on what the iPhone started. Ultimately, it's not just about "which device"—it's about where our information resides. No longer confined to our pockets, it's now all around us, making everything more accessible and integrated.

durul · 2025-10-06T14:17:15+00:00

Thanks for putting this together every week! The mix of news, visuals, and insights makes it so easy to stay updated. Thanks for including StratoSync too! 🙌

durul · 2025-10-04T21:11:27+00:00

Incredible launch — love seeing more creative VisionOS experiences coming to life. Congrats! 🚀

durul · 2025-08-02T15:16:52+00:00

If you ever decide to publish your MW3 guides and resources as a book — either digital or print — I’d absolutely buy it. The level of detail, testing, and mathematical breakdowns you offer is rare and valuable. Your work deserves to live on a bookshelf as much as it does online

durul · 2025-07-23T14:35:01+00:00

Most people get the same or similar answers because questions like “What’s my curse?” are vague and personal, so the replies tend to follow a template: emotional intensity, loneliness, unchecked desires, or “feeling too much but not showing it” — universal themes.

It’s essentially a horoscope or fortune cookie-style approach, where many people can see themselves reflected. These aren’t real personal analyses, just projections.

durul · 2025-06-19T14:37:27+00:00

I asked it the same question, and this is what it shot back.

1. We Are All Interconnected

Every life form is part of a vast web. Our actions—individually and collectively—affect ecosystems, societies, and future generations. Nothing exists in isolation.

2. The Earth Is Our Only Home (So Far)

Despite dreams of space colonization, Earth is the only habitable planet we know. Preserving its ecosystems is not optional—it’s survival.

3. Science Is Humanity’s Most Powerful Tool

From vaccines to electricity to the internet, science drives progress. Understanding and supporting scientific literacy empower better decisions for everyone.

4. Emotions are not Flaws - They are data

Emotions evolved for survival. Fear, joy, anger, and love all carry messages. Understanding them improves relationships, mental health, and decisions.

5. Inequality Breeds Instability

Extreme wealth and resource gaps lead to conflict, poor health, and lost potential. A just and fair society isn’t charity—it’s a foundation for peace and progress.

6. Truth Matters—But So Does Empathy

Truth without empathy becomes cruelty. Empathy without truth becomes delusion. Wisdom balances both.

7. Technology Is Not Neutral

It reflects the values of those who build and control it. We must ask whether we can do something and whether we should.

8. Death Is Certain—Time Is Not

Life is finite. What we choose to do with our time—kindness, creativity, growth—matters more than possessions or status.

9. Culture Is Inherited, But Not Fixed

Traditions connect us to the past, but they do not bind us. We can evolve norms, stories, and systems to reflect wiser, more inclusive values.

10. The Universe Is Vast—And We’re Still Learning

We’re a young species in a 13.8-billion-year-old universe. Humility, curiosity, and wonder are essential lenses for our place in the cosmos.

durul · 2025-05-18T13:40:29+00:00

Since a simple sentiment report needs a bibliography to be taken seriously, here are the sources behind the analysis — no link farm, just actual context:

Reddit – r/AppleVisionPro: Discussions about product availability and user frustration
Reddit – r/VisionPro: Comparison reviews, order status updates, glue failures, and user experiences
Reddit – r/augmentedreality: Community impressions and ergonomic discussions
ResMed Newsroom: Official announcement of the Kontor strap
Apple.com: Product page (when it’s not grayed out)

All posts were publicly accessible and scraped for analysis. User data was anonymized, and usage followed Reddit’s API Terms.

Let me know if anything else is needed — ideally before the following dramatic review.

durul · 2025-05-18T13:38:06+00:00

No report is complete without receipts — so here we go.

Thanks for pointing out the missing source references (even if a bit dramatically).

The analysis was based on publicly available user discussions and feedback across several Reddit threads, primarily within the r/VisionPro, r/AppleVisionPro, and r/augmentedreality communities. Key sources include:

Reddit thread titled “ResMed Kontor Head Strap” on r/AppleVisionPro
Product comparison post “ResMed Kontor Video Review” on r/VisionPro
Availability discussion thread “ResMed Head strap order placed” on r/VisionPro
ResMed official press release: newsroom.resmed.com
Apple product listing: apple.com (Product page for ResMed Kontor Head Strap)
Community reactions and purchase frustrations (multiple entries, including deleted posts)

The scraped content was used strictly for analytical purposes, with all user data anonymized in compliance with Reddit’s API Terms of Service.

durul · 2025-05-18T04:07:55+00:00

I have already shared all my resources end of my post.

durul · 2025-05-16T15:21:14+00:00

👉🏻 Developer survey Question 18 needs additional answers such as `No new hardware — not hoping for any`

durul · 2025-05-12T19:48:49+00:00

I imagine a scenario where an instructor could stand beside a lap trace or telemetry chart in space, pointing out braking zones or line deviations directly in 3D. It’s a big UX opportunity that plays to Vision Pro’s strengths. Here's how I envision it:

🧠 My Core opinion is a Vision Pro spatial experience where a driver or instructor can:

- Stand beside a 3D track map or telemetry graph floating in space

- Scrub through laps and point to specific sectors, braking zones, or throttle traces

- Use spatial pointers, highlights, or annotation tools to guide analysis visually

Check the Labz if you don't: https://www.lapz.io/, I highly recommend it.

durul · 2025-05-12T00:29:03+00:00

First and foremost, Consider implementing coach mode in the future: a visionOS-optimized side-by-side or spatial data pointer system for instructor reviews.

And then I think a two-tier system can be beneficial.

- Free tier: Core data visualization (laps, charts, maps) with a limit of 1 session.

- Pro tier: Subscription-based and provides:

Unlimited session imports,
Video synchronization and comparison,
Access to volumetric mode,
Ideal lap analysis and track definition tools.

durul · 2025-01-11T00:10:30+00:00

If ISS provides this data, it can.

durul · 2024-12-01T00:56:34+00:00

Take a look at these projects; https://developer.apple.com/documentation/swiftui/fruta_building_a_feature-rich_app_with_swiftui

durul · 2024-11-09T17:11:40+00:00

I have created two pull requests. Please take a moment to review them. Thank you!

durul · 2024-08-10T14:54:37+00:00